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OP here, we believe that the time has come to let remote workers and highly agile teams get stuff done together in a very different and much more natural way. CoScreen is a remote collaboration tool that enables exactly that.

Problem: Pretty much anyone who has ever worked remotely knows it - today’s remote collaboration solutions provide much better screensharing quality and reliability (thanks, Zoom) compared to a few years ago. But it takes the same frustrating steps to connect and to pick windows again and again, only one user can share screens and remote control at a time, users have to ask for permissions to interact, etc.

Solution: By turning your secondary display into your team desktop, CoScreen enables you to share your windows with your peers in a single, natural interaction step by drag & drop. Any windows you drag to your extended screen are shared with your peers. They can share their windows in the same way, on the same desktop, side-by-side, at the same time. Each team member has an own mouse pointer and can interact with all windows without having to request controls. It also works great if you only have one screen and you can also chat with each other via audio.

CoScreen launched on Product Upcoming with a private beta a few months ago with over 300 sign-ups and early testers from small startups to large tech companies. Since today it is in public beta and you can use it for free by going to coscreen.co.

We can’t wait to hear what you think as it’s still an early beta version and while it’s still rough around the edges. Till & the CoScreen team

How much does it take to pay a hunter on PH in order to be featured these days? asking for a friend.
I think the go to rate was $5k, this is maybe 6 months ago. It was a friend who told me after they asked a famous ex-Uber employee to hunt them
That's why I have never found a single useful product on ProductHunt for years now. It has become an absolute farce that it should be illegal.
I was just thinking how much PH has turned to shit lately when I saw this in #2 spot today:

https://www.producthunt.com/posts/linkbuildr-for-wordpress

Really? A Wordpress "Linkbuildr" that automates spamming emails when you write posts? And nothing but praise in the comments? PH has become a joke and we definitely need some ethical competition in the product discovery space.

Couldn’t agree more. Yesterday I was browsing the top product of the day to see what future competition was like and the product was a color swatch that gave you similar colors for inspiration. It looked like they mashed together a codepen with a color swatch api I’ve starred but I won’t even bother linking to here. It’s sad for sure.
Could it be that there aren't that many exciting new products coming out? Or is that blasphemy?
But there are a lot of new exciting products.
Where do you usually come across them?
Hacker News, lately, because I don't come anywhere else. I'd say I find a good product every 5 days.
Would love to know that as well ;) Our hunter had signed up to our private beta launched via Product Hunt Upcoming and that's how we got connected.
What do you mean? You can hunt your own product on PH now!
How are you different from Vectera.com which does the same thing, but with persistent rooms too?
Thanks for your question! Afaik Vectera runs in your browser and focuses on sharing what's in it. CoScreen lives on OS-level so you can share and interact with any native window, browser or not. They also don't seem to support multiple users sharing windows at the same time side-by-side but please let us know if we're missing anything.
Congrats on the launch. This looks like one of those great ideas that works so much better than the old way that it feels obvious in hindsight.

I’m curious how you handle different monitor resolutions?

Thanks a lot for the kind words! Great question, CoScreen shows shared windows based on their relative positions and sizes. So they appear in the same way for all participants. If there are huge difference between resolutions, the users will see either very small/large fonts but we still concluded after many prototypes that this is the best tradeoff. Feedback welcome nevertheless...
So what you're saying is, you don't handle different monitor resolutions.

My team is split between people with 4k or even 5k screens and wide-angle screens with lower pixel densities, so this would be an issue. Not sure how common that is, though.

Sorry for the misunderstanding - We do handle the translation of resolutions to create the same layout for everyone. In addition, you can actually pinch zoom into remote windows if necessary.
Got it. Awesome!
Seems like a great idea. One question is visual data only shared among peers or does it pass through your servers?
Thanks! It goes through a central server so it can make it through corporate firewalls. This adds latency unfortunately but makes it more reliable for folks behind strange proxies and scales better for >2 users. But in any case, we'll enable P2P connections shortly so it won't go through the server if it doesn't have to, stay tuned. Sign up on our website and we'll let you know once it's out.
If you haven't already, you might consider adding end-to-end encryption, which will make people more comfortable with it going through your servers in the cases where it still needs to.

Also, I'd assume you use video compression; keep in mind that encrypted video still reveals some information through sizes, especially if you have some idea of the kinds of applications users typically use.

Absolutely, it's already end to end encrypted but good point on metadata...
I gave up in fustration, the site has no real information, no system requirements, no installation information. does it run on linux? I like the idea but i have a department with 100 fedora workstations in it.
I am feeling the same way mate. I believe it’s only for macOS.
Thanks for your feedback, sorry if that wasn't clear. We'll fix our website. It's indeed macOS-only for now (we had to start somewhere). Here all steps to get started: https://support.coscreen.co/portal/kb/articles/getting-start...
Naw mate. Your good. I read the site in English and it said clearly macOS. No need to apologize. I was just trying to be nice. Site was cool. Maybe more documentation. Good luck to you.
Thanks as well, it's macOS-only for but we're working on other OSes. It should work on anything that runs macOS Mojave and higher and at least on 5-6 year old Mac Books.
I'm curious how many Mac users have multiple monitors? I don't think I've ever seen a single one (I'm sure they exist). I see iMac users on one big monitor. I see MacBook/Air/Pro users either on their laptop or one monitor, usually with their laptop closed.

Where as pretty much all Windows users in game dev seem to have 2 or more monitors.

Are you expecting lots of mac users to buy a second monitor or use an iPad for this second monitor or is my experience just atypical and lots of mac users have 2 monitors?

Professional Mac user here.

Over the last decade, I’ve worked in shops supporting Macs (as well as other OSes) along with other Mac-using developers and designers.

All my Mac-using colleagues have dual-or-higher monitor setups.

Thanks both. In corporate environments we've seen more software developers who have a Mac with multiple screens (often one of them vertical for code) than with just one. But we were unable to find any reliable stats and it's an ongoing debate in how far multiple screens (vs. just hire resolutions/more pixels on one screen actually improve performance - see https://lifehacker.com/is-the-multiple-monitor-productivity-....

In any case, CoScreen also works great with just one screen and you can share/unshare with a single tap of a button.

Every person in my company uses a Mac (~100 people) and I think only one person uses only one monitor. Every employee gets a 34in LG and a laptop stand and every person (except the one) uses the laptop open to the side for extra stuff. I know at least two employees have several external monitors. One of them has two 34in and a thunderbolt display (which is ridiculous to me, so much head movement).
Thanks a lot for the helpful data point!
Btw, we've just set up this form to get quick feedback which operating system we should support next - please help us prioritize! https://shorturl.at/koJX3
UPDATE 1: Thanks so, so much for the huge interest & valuable feedback, please keep it coming!

Here's a quick form for the many folks interested in Windows & Linux support, please help us prioritize: https://shorturl.at/koJX3

UPDATE 2: As mentioned further below, we're also on Product Hunt today - check it out (and let's beat the boring marketing apps): https://www.producthunt.com/posts/coscreen

Not even remote. As a nontech worker its unbelievably helpful in a shared office too.

I used to have a big screen tv and 2 keyboards and wireless mice at a coffee table in my office for just this problem, and a crazy (for normal humans) hdmi splitting setup that allowed for a byod of sorts.

Great idea!

MPX, multi-pointers on X11/Linux systems was amazing, back when it first came out around 2005, and definitely seemed like the future of collaboration. I'm glad that someone's making a go at productizing the concept and building a company around using it for collaboration. it gets me sad to see cool tech languish add research projects because of barriers, whatever they may be, to have a sellable product. Some make it though; Ksplice is one such product that had a successful company and exit that I can think of.
i'd like to use this in a classroom setting where either every participant, or the moderator/teacher can see all shared windows but decide to feature only one or two of them.

one way to do that would be the ability to minimize shared windows.

the teacher (or anyone with moderator privileges) would be allowed to minimize windows, but also have a way to look at windows while minimized (as a teacher i want to see what everyone is doing on their own windows, while at the same time get the students to focus on a particular window.)

Great idea, we're already looking into educational use cases. Feel free to reach out directly if you want to discuss this further.
This looks like an amazing idea executed brilliantly–reminds me of Dropbox in that way.

But I've been thinking about it for the last five minutes and I cannot figure out how you guys actually managed to implement this. What sorcery is at the root of this? How do you composite windows from two different machines into a single desktop on macOS?

I assume it's not a real desktop, but a full-screen window of their app. And I guess it basically works via two-way machine control. Each person's computer is actually driving their own windows, but the software allows everyone to control everyone's (shared) windows, just like one-sided remote-control apps. It's a pretty clever idea!
Thanks both - here's how it works: 1. CoScreen captures each of your window to be shared individually. 2. It sends them across in a combined video feed per user with window positions & sizes. 3. On the receiving end, it creates actual native windows which are filled with the video streams of the corresponding windows. That way they look and feel like actual local windows. E.g. you can move & resize them like any other native windows. 4. Whenever you click or type into a remote window, the input is send across to the origin of the window and applied there.
This is so good!

How does it work with selecting text and copy-pasting? In the Sublime Text example, can Bob overwrite Alice's clipboard.

We're still figuring this out and will probably get inspired from remote desktop solutions. But reach out to us if you have specific ideas
If everyone could have separate clipboards, but still copy from and paste into each other's windows, that would be ideal.

Also: this would be a major feature request from me. The ability for me to paste code into someone's else text editor (or copy out an error message) when I'm helping them would be a major productivity boost.

We hear you and will prioritize this. Some remote desktop and virtual desktop solutions enable you to choose local or remote clipboards through a slight tweak of the traditional/locally applied shortcuts (e.g. Command + V), we'll check this out as well.
My hunch is it uses the MacOS accessibility APIs.
I want to see the actual product. Cool animations but a picture is worth 1000 words
The intro video on the homepage shows the actual software in action at around 53 seconds (mouse over the video to unveil the seek bar).
I thought this was vapourware.

The best video you can show for this is your JIRA board where everyone can update it in realtime in a team meeting with remote teams.

Don't bother with the animations, they make your product look not real! Very impressive.

Thanks for your feedback. We felt that it's hard to get the concept across without showing both clients. But thanks again for the input, we'll show the real interactions more prominently.
If you just show people using it for real work you will be okay
My initial reaction was, “no, there was no video on that page,” so I went back to look.

A lot of browsers disable audio on auto play videos. The fact that the controls are also hidden and the background color being the same as the website, it just looks like an animation, not a video. So some icons move but the meat of the video doesn’t start until after people will have disengaged.

Thanks for your feedback, we'll fix that...
So you have to wait until 2/3 of the way through the video to see the actual software.
Thanks for your feedback, we'll add screenshots more prominently to reduce the wait...
MacOS only. Leaves me (Linux) half our devs (Windows), all of our execs (Windows) out.
Yes unfortunately and yet only for now. We just started with Mac (coin toss) and now we'll do our best to cover all of them soon.
That's sad -- from your demo video, I thought you were supporting Windows too (the minesweeper window). You might want to make that more explicit.
Point taken, we only have a raw windows prototype so far.
Hey both, we were overwhelmed by the interest (and therefore also wrt. requests for Windows & Linux support) but we've just set up this form to help us prioritize the next platform CoScreen should run on: https://shorturl.at/koJX3
I am worried about screen sharing. Who knows what I could browse at work. I don’t want to mistakenly share my credit card number.
Even with CoScreen you only share screens/windows when you want to. You can go online/offline with a tap of a button and in any case it only shares windows on a display you choose.
This is a very serious security concern, in my mind. I regularly type into the "wrong" window, due to (pick one) poorly designed UI or my stupidity.

This is mostly harmless in my solo environment, although one does have to be careful about things like .bash_history and websites that might actually be listening for keystrokes and sending them upstream. Having a team window seems like it would make this a greater risk.

On a different topic, I'm one of those people that can't stand pair programming and related--it destroys my ability to concentrate deeply on the problem in front of me.

I'm curious why somebody would start with a machinetosh? Windows is used way more than machinetosh on developer machines.

Is it because:

1) Authors don't know the demographics?

or

2) They think that Windows users wouldn't pay? (Not true I think)

or some other reason?

it might be a technical reason sometimes. Does windows provide an API for you to capture a window, instead of a desktop on a specific screen?
True, just in this case we just went with Mac because we used it personally. Windows might actually have been easier because macOS gets increasingly restrictive (e.g. with Catalina). Nevertheless, glad we made it and we'll do our best to support all major OSes.
I don't want to make this a game of one upmanship but I'd be surprised if there are GUI things you could do on a machinetosh that you cannot do on Windows.
Agreed, hopefully Windows will be easier though. Getting mac done well gets harder with every macOS update...
Windows APIs give great info about size and position of windows. Challenging part is really the per monitor scaling, but it’s not impossible either. Great product, top work
Thanks for confirming & your feedback!
looking forward to using this once it rolls to linux
Btw, we've just set up this quick survey to help us prioritize operating systems. Feel free to sign up & we'll keep you in the loop...
Thanks for the question. It was honestly a close call and we knew we couldn't do both at the same time (this is a side project).

The reasons where:

1. Our personal devices were Macs at the time we started.

2. We felt that the first use case for CoScreen would be agile developers who collaborate with UX designers. The latter seemed to mainly use Macs (https://austinknight.com/writing/designers-prefer-macs) while the former are mixed e.g. also depending on the region. In the SF Bay Area Macs quite popular among developers so we ran with it.

In any case, we hope to be able to support all 3 OSes soon. For that reason CoScreen was built 95% in a platform-agnostic way (nwjs) so we're optimistic.

Does that mean you use the JS Screen capture api to capture each and every window separately?

I would’ve thought that’s too much for typical (laptop) cpus but have to admit I never tried this

We're capturing them natively and are working on another major performance improvement which should make it at least as efficient as other major solutions.
Are there other solutions that capture multiple windows at once? I’m only familiar with typical screensharing where the use case is either full screen or a single window.

The way I understand you, coscreen captures each window shown individually.

Doesn’t that also mean that overlapping windows are captured in full? I can’t try it out atm so perhaps if you could leave a comment on cpu usage for encoding as well as bandwidth (upload) compared to a typical Screen Sharing solution with a single screen that would be great.

I’ve been toying with the idea of getting a MacBook with cores > 4 for precisely that idea: capturing every single window, streaming them out to a separate machine for analysis of what’s happening in them and possibly making them accessible for collaboration as well, all without losing too much performance

I believe somewhere in this area is a lot of productivity waiting to be unlocked with better tools, not just for typical remote use cases but for any kind of office work

We do capture overlapping windows separately but we turn them into one video feed with overlaps to save bandwidth and overhead. We might stream windows individually but feel free to reach out directly if you have specific requirements & ideas.
It's not called a "machinetosh". It's Macintosh, or Mac for short. Named after the McIntosh variety of apple (https://en.wikipedia.org/wiki/McIntosh_(apple)).

"Windows is used way more than [Macintosh] on developer machines." - Citation needed. Macs are extremely popular among web developers, and are required for iOS developers, both pretty major categories of "developer".

Thanks for the historic context ;)

Edit: + Stats from the Stack Overflow Developer Survey 2019

Windows: 47.5% MacOS: 26.8% Linux-based: 25.6%

Source: https://insights.stackoverflow.com/survey/2019#technology-_-...

You seem pretty grounded in facts, I hope you and your product go a long way. That said, this number isn't representative. Lots of enterprise devs (using Windows) are the kind of people who don't go to SO or fill surveys. I'd bet survey age group would be skewed towards younger crowd. In fact, I'd wager it's something like 75 15 10 Windows Mac Linux.
From a security standpoint can you discuss the life of my data as it goes from my computer, through your service, and into my coworkers computer. What is stored where? Who at your company can access what? Thank you in advance for any information you are able to provide.
Hi there, we're capturing windows at the client, send them across through our video bridge (to get through proxies & firewalls and scale beyond 2+ users per channel) and then the windows are shown on the remote end. We don't store any shared windows, videos, images, or audio data. We only capture anonymized usage stats to get an idea what we need to optimize for (e.g. # of sessions and users per session).

Our security concept was recently approved after an extensive vendor risk assessment by a large global enterprise. This is a positive indication but obviously don't hesitate to drop us a mail if you want to discuss specific requirements!

If there's one thing I can't stand in a screen sharing app (I'm looking at you, Slack and Zoom), it's annoying overlays.

I want to be able to open up my IDE, go full screen with it, and have zero overlays visible.

The only tool I've been able to find that lets me do this is Tuple (tuple.app), which is the closest thing I've found to Screenhero (which was my favorite screen sharing and pair programming app back in the day).

Agreed! Soon CoScreen's UI controls will get hidden automatically so you won't see anything but shared windows.
That's awesome, and I'm glad to hear it!

If I could make a tiny suggestion: Why not hide the coscreen functionality under a little system tray icon with a pop-out menu? That way, it's invisible, but still easy to get to.

Good point, we had thought about it but wondered if users would find it. But we'll look into it based on your feedback...
Zoom's overlay controls are pretty great too
What if I only have one screen?
"It also works great if you only have one screen"
Where do you see that? I can't find that on the page.

Also, how?

Great question - here's how it works: If you only have one display (e.g. while you're on the run) it can still share the windows on this desktop but you can share/unshare all of them with a single click on the display icon next to your user. You can also auto-minimize all your windows when joining a room.
Ok so it's an all or nothing type thing? I'm either sharing my whole screen or none of it?

Still definitely useful! Just trying to learn the limitations.

This is awesome by the way, I'll definitely be checking it out!

Exactly - all your windows on your screen to be specific, so e.g. not your desktop background or files on your desktop. We're considering adding the ability to pick individual windows but feedback welcome...
On the Mac, could you assign a "spaces" virtual desktop to be shared with coscreen? Then you can just 3 finger swipe between a private screen and the shared one.
Could do this with windows 10 and its "virtual desktop" too!
Yeah we're considering this as it's indeed quite consistent between mac & windows but it will take a while to figure out...
This is a great idea, and your implementation of it looks awesome! I don't have a use for it at the moment, but I'm bookmarking it for later.

A bit of feedback on your website: the yellow you've chosen is nearly impossible to read on my monitor, especially with the thin font used in "Sign up".

Thanks for your feedback, we'll fix that asap...
This looks like a cool product if both people have a secondary screen.

A similar but much more low-key solution that I love using is tmate[1]. Tmate is a tmux session that can be shared over SSH. It's super easy to install and anyone who has a SSH client can join in two seconds. It's great for pairing sessions if both developers are into vim or emacs editors. Or just to show a quick thing.

[1]: https://tmate.io/

Thanks for sharing! It's true that CoScreen works best with multiple screens but it also works with just one screen (details in a comment on this thread). Tmate is indeed awesome as long as you're working within Terminal.
Does this require installing a software on your computer? Or is this purely browser based? Or is it Java?
It's a native macOS app you need to install, other operating systems and a web client will follow!
This would be very nice to have up and front on the landing page. I bent over backwards looking for OS compatibility.
There are two job positions to join their team as well. I guess they could even use their own tool during a test interview.
Pricing info would be great, free during beta is nice but for my company at least we would need to know the cost upfront.
Fully understood, we haven't finalized it and it will likely be free for at least 3 months but then it will likely be in line with Slack, Zoom, etc.
Looks like a pretty neat product. Congrats on the launch
Some cities have meetups doing coding katas using pair/mob programming. Eg [1]. Perhaps a demo opportunity? Though the mac-only could be an issue.

Fwiw, doing a 3D "desktop" on linux a year ago, I was pleasantly surprised by electron's desktopCapturer for visuals. But multi-source input... X was ok-ish, Wayland not.

[1] https://www.meetup.com/Boston-Software-Crafters/

Great idea! We'll follow-up.

Also thanks for the hint, we'll use it as a starting point for Linux

This is brilliant. Super easy mental model. Super easy to use (just drag and drop!). No friction. This is going to be big, whether it's you guys (hopefully!) or someone else that steals this idea (boo!)

And I wouldn't pay too much attention to the Windows/Linux users in the very early days if it's too much of a development burden. There are tons of tech forward companies that are mac-only that are a large enough market to build momentum.

If the windows/linux people want it make them put their money where their mouth is and charge them in some way. It costs nothing for them to say "Build this for me!" but they already have enough info from the demos and mac app to make a purchasing decision. So if they're serious get some money from them. If you do a pre-order and say "if it's not released in 3 months you get your money back" that should be enough signal to know if they really want it or not.

Congrats! Not many people make something this good. Now don't screw it up :)

And if you're not part of YC already you should do a late application for the W20 batch.

Thanks so much, feedback like this makes this worth it! We'll do our best and thanks for the great advice!
I bet Linux is not even possible. How do you force windows to be at the same location across different systems. I use i3. There are plenty of other tiling managers. This is not gonna be cross-platform. Just my two cents.
Afaik each OS has hooks that lets apps with the required permissions set the location & measurements of other windows. So we're optimistic but obviously we're not done yet.
Shouldn't be too hard. The wmctrl package, for example, supports a whole bunch of different window managers.
i don't know how it works on macos, but for it to be useful, windows don't have to be at the same location.

on my computer i select the windows i want to share. each of those windows could be sent in a separate stream to the remote machines. and likewise my computer could receive independent streams of multiple windows. this way i could arrange all windows as i see fit.

the alternative is that the app takes over a full screen and the shared windows are rendered within it. then the app is responsible for window placement and can implement its own way to arrange windows as it sees fit, and share that location with its peers. a window manager within a window manager, of sorts. something that many windows applications like photoshop already do. linux/unix could do that with Xnest already more than 30 years ago. nowadays there is also xpra, which can mirror windows across multiple screens. i don't know about wayland, but i believe it should be possible there too.

What's a "tech foward" company? I just migrated from Apple (10 year user) to Windows 10. It's rare to see a good tool not available cross platform nowadays.
Excellent idea, brilliantly executed.

But as a CTO, I would be concerned about the security implications.

It makes sense to route traffic via a central server because P2P does not scale to large numbers of participants (which is why things like the Jitsi Videobridge exist despite WebRTC P2P being a thing), but it means your customers have to trust you not to get hacked, be compelled to, or otherwise misplace/record sessions.

Since peers can interact with the remote windows, this is basically a remote control tool, and getting hacked also means being able to inject keystrokes or otherwise compromise clients (as recently demonstrated by TeamViewer). For security-critical things like SRE work this is a particularly big concern.

Adding end-to-end encryption would alleviate some of these concerns and reduce the attack surface to implementation mistakes or compromised software updates, which is far easier to reason about.

Perhaps it's not a concern for a small startup, but it's definitely something larger companies worry about.

Please add support for other platforms and add end-to-end encryption, because I really want to use this!

As suggested by someone else, we would definitely pre-order licenses for Linux and Windows.

I am pretty sure that E2E encryption is impossible today if you are using a WebRTC SFU since there's no spec for it. The closest thing is PERC Lite [1] which no browsers support, though maybe you could cobble something together native.

Is there some path I didn't know about?

1. https://www.meetecho.com/blog/meetecho-and-cosmo-strike-agai...

I don't know about browsers, but I know that Signal implements E2E-encrypted phone calls using WebRTC for signalling.
WebRTC does not do signalling - that is the one part that you always have to provide yourself. WebRTC provides the peer descriptions and ICE candidates that you need to transport to the other party/parties.
Thank you for the in-depth feedback. We're actually using Jitsi as videobridge which comes with encryption built-in but we hear your concerns and security remains a priority for us despite our early stage and we're also working on various OSes.
> P2P does not scale to large numbers of participants

I'm curious about this statement. Intuitively it seems there is already an algorithm to near-optimally distribute updates to a sparsely connected mesh network. You'd want two or three connections from each peer to another, not N:N. Optimal is not necessary as long as you have at-least-once semantics on message delivery; a node can just ignore messages it's seen already, as long as it's not too often. Is there a name for this existing algorithm?

On top of that you could overlay a symmetric session key and you'd have full E2E. Then central server would be session initiation only--which could still do authn/z to hand out session keys--and billing/metrics.

My concern about security is that this would be used like Slack, but for apps -- always on, sitting in the background, occasionally has my attention.

If I drag an app that has an integrated terminal (e.g., VS Code), could one of my teammates start rooting around in my filesystem?

It wouldn't be too hard to use Slack status to determine a time to do this when the other people sharing are not online/not watching.

This could theoretically happen but you can also choose to stay passive/appear offline with a touch a button and if you are online/sharing you can see a faint glowing border & hint around the specific display. We've already considered to use other clues to help and will look into this, great feedback!
Very good idea I love it! I foresee and amazing future for you, just don't give up, keep it going for as long as you can. Cheers!
Thanks a lot for your support!
Love it. Hope you eventually have an Ubuntu client.
We'll do our best, please keep bugging us on this ;)
How do you handle/plan to handle accessibility? If it grows, Sooner or later, a company which needs a11y for legal reasons might consider your product, so it's important.
We're actually using macOS accessibility APIs to manage local and remote windows and are therefore optimistic we can sort this out - eg by moving windows via keyboard. Detailed requirements are welcome!
Is it possible to default to sharing in read-only mode?

I've got plenty of stuff I'd be happy to share with other people to let them look, but I don't want them messing things up.

I'd be fine allowing them write access on a per-user/per-window basis, but I'd like to default to read-only.

We decided for an "open-first" approach unlike most other apps but are considering adding a flag to configure this. Feedback welcome!
So basically this just turns a second display into a screen share where multiple users can share their app windows? Seems like this could have been tackled 95% with existing open source software and supported on multiple platforms.
Given that another commenter likened CoScreen to Dropbox in that it is an "amazing idea executed brilliantly" it seems only fair that they've already got their very own Dropbox comment now.

95% isn't 100%. A mere assemblage of tools isn't a finished, polished, well-designed, reliable product.

Thanks both, time will tell if we have the remaining 5%!

Obviously we'd love this to be as legendary in 12 years from now ;)